Sharpening unit



s. G. NICHOLS SHARPENING mm SejitQ 20, "1949.

. 2 Sheets-Sheet 1 Filed Dec. 26, 1946 will! III/fl! I Ill/ll(Ill/fill!!! Ill Ill/ll SHARPENING U T Filed Dec. 26, 1946 :2Sheets-Sheet .2

Patented Sept. 20 1949 UNITED STATES PATENT, urn-E Stephen G. Nichols,Winchester, Mass, assigns:

to L. 0. Nichols, Newton, Mass; at firm My invention relates generallyto. grinding ap- 7 tinuous service and, accordingly, in frequent need 7,1

of sharpening, and whrespeed and accuracyin thegrindingoperationisimportant. a

Another prime object. of my invention. resides in the provision ofsafety means so that there can be no degree of injury to'any'personusing my sharpenen. A further feature. is the provision of bladeholdingand knife seating means 50 positioned in relation to the grinding wheelsthat an efiicient sharpening may be. imparted to knives of various size,thickness. and length,

An additional object offmy invention is to con struct my sharpener in.the. form of. a portable unit which may be ofconvenient si'zdjshape, andweight to be easily carried from one location to another, which. may beplugged'in to any usual electrical outlet, and which can be positionedon any counter, bench, shelf, or table.

Heretofore in devices of this' kind ithas been customary for operatorsto grind or sharpen knives on an open and unguarded unit, which has froma practical standpoint necessitated: highly skilled workmanship, ifefficient and satisfactory results were to be obtained. Otherwise, poorcutting edges resulted, knives were damaged, replacement. costs werehigh, and accidents were numerous. Unskilled workers, therefore, wereun-. satisfactoryto perform such work.

In my novel unit, however, the operator has merely to position the knifewhere indicated through the opening, provided. in the coverguard and toguide, it back and forth across the grinding wheels. There. i littlechance for error, injury, or mutilation of the blade and, therefore,this work may be. performed by unskilled operators- Further features,novel improvements. and advantages. willv be. hereinafter more fullypointed out andclaimed'. V Referring to the drawings. wherein]; show apre-' ferred embodiment. of my invention:

' ings 22-42,, whichmayl extend thru the top H3 Application December 26,194.6, Serial No. 118,541

' 1 Claim. (01.1 51-80) Fig. l is a front elevational view of mycomplete unit; a

Fig. 2 is a plan view partly in. cross-section, showing the. grindingmechanism, and

Fig- 3 is a front end view with the cover and base in crossrsection.

I prefer to form my portable power grinding unit-with the bottom.portion enclosing a suitable motor such as a one-quarter horsepower orother fractional power electric unit and with a plurality of grinding,wheels supported; in the upper part- One setof the grinding wheels isconstructed and arranged for adiustment toward and from the. other tocompensate for wear and has a suitably'hinged cover to partially encloseand protect the grinding mechanism.

In the drawings,'a suitable electric motor is designated. generally at!and isseated on a suitable bracket. and.- secured thereto by screwsl2.-I2, said, bracket [1 inturn being. fastenedto the bottom. portion[43 by bolts [3. The motor [0 is housedwithin the box likecompartmentvcomprising the bottom LL, sides ll5'f5,, top l6, closed end. HI, and.the opposite. end l8 cut away to permitaccess, to the motor [or The top[6 is braced by a plurality of'supporting standards f9;

A base 20, which supportsthe grinding apparatus, formed with adependingflange portion H which rests. upon thetop [6 and. is attached thereto ateach corner by suitable belts or fastenand thru thesupporting. standards[9. Extending upwardly from the base 25-. at. each are arms 23 and...24;. Suitably journaled. in these frames 23 and 2d are. a pair of shafts2'5 and. extending from one frameto the. other, each proiecting beyondthe frame. 24 and carrying on their respective outer ends gears, 32 and.33. J ournaled bearings for these shafts. are. indicated. at &434 in theframe 23, and at 35-45 in the frame 24'. On the shaft 25 is a pulley ((1which. i driven by a v-belt' dfl; extending, downwardly to, acorresponding driving pulley on the motor til, as, indicatedin-idottedlines-at M, Fig. l. j

Thus the. motor will drive the, pulley 4B and, with the gears 31 and.mesh, will drive said gears. inthe. direction shown in the arrows.Fig... 3.. Mounted above the gear 32 in the frames 23' and Z4 isacountershank I5 adapted to rotatei'n suitb'earingmdndicated at and 41,in the upper part of th frames 23 and 24, respectively, saidcountershaft extending beyond the frame 24 and carrying a gear 48adapted to mesh with the gear 32 and rotatable in the direction of thearrow, Fig. 3. Thrust collars 49-49 hold this countershaft 45 inposition, and mounted on said countershaft are a series of grindingwheels 59-50 of equal diameter, and a special grinder 5| of smallerdiameter, as will be further explained.

These grinders 5|! are, preferably, held in spaced relation bycylindrical washers or hubs 55, with end pieces 55 and 51 to hold thegrinding wheels in proper position and clamp the same on the shaft 45 sothat the grinders will rotate therewith when driven by the gears 32 and48. A cooperating set of grinding wheels 6U59 positioned on acountershaft 59 and a special grinder of smaller diameter 6| arearranged with similar spacing washers 63 and in staggered relation withthe grinders 59 on the other countershaft, as just de- 2, except for thespecial grinders 5| and 6 I, which are of smaller diameter-and areadapted to con-' tact with each other, ornearly s0.

The countershaft 59 carries a pinion 64, see Fig. 2, which is arrangedto mesh with the lower gear 33 and will be rotated in the direction ofthe arrow, Fig. 3, so that'the complemental grinders 5G and 69 are thusrotated in opposite directions, .as well also as the end or contactinggrinders 5| and 6|.

In order to afford relative adjustment between the grinders 50 and 60,1mount the countershaft 59 in suitable journaled bearings 65 on each endof the upper arms 66 of a bell crank yoke 61, having said arms 65mounted on the shaft 39, which shaft 39 carries the gear 33 as abovedescribed. The yoke 61 is constructed and arranged for adjustment of thecountershaft 59 to move the grinders 60 toward and from the grinders 50for adjustment or to compensate for wear. Thrust collars 68-458 willhold the countershaft 59 in desired lengthwise adjustment, as shown inFig. 2.

To rock the yoke 61 on its hearings on the shaft 39, I provide a forkedhub 19 at the center of the yoke 61, thru which hub 10 an adjustingscrew "H is fitted, with the 'shank of said screw H 4 The adjustingscrew 85 has a threaded projecting portion extending beyond the collar82 and being threaded into correspondingly tapped hubs 8888 of knifehandle guides 90-99 by right and lefthanded threads, so thatmanipulation of the adjusting screw 85 will move the guides 99-90 towardor away from each other. The position of the adjusting screw 85 isarranged substantially in alignment with the contacting faces of thegrinders 5| and 6|. These guides 99 constitute an automatic positioningand guiding gauge for the knife handle so that the operator can hold theknife blade into sharpening position on the overlapping grinders 50 and60.

With the contacting grinding members 5| and 6| in alignment, the extremeedge portion of the blade adjacent the handle can be effectivelysharpened, the operator simply rocking the knife blade slightly topermit this sharpening action on the blade adjacent the handle. This isan important and novel feature which cannot be practically performed onordinary grinders of this general type, so far as I am informed.

Thus, the operator adjusts the shaft 85 so that the guides 95 willsubstantially span and fit the handle of the knife being sharpened;the'motor ii] is energized from any suitable source of power by pluggingin the wires or switch (not shown), and the adjustment, if any, on theyoke 6'! being effected by manipulating the adjusting screws 7Thereupon, the operator fits the knife handle thru the guides 90,bringing the blade down on the overlapping portions of the grinders 59and 60, drawing the knife slowly once or twice back and forth across thegrinders to effect the sharpening action, and thereupon swinging theknife handle down slightly to insure the operation of the contactinggrinders 5| and 6| on the edge of the blade next to the handle, and thesharpening is completed.

In order to provide a protecting guard and guide for the rotatingsharpening elements, I arrange a cover 90 pivoted at 9|--9| to upstand 7ing lugs 92 formed on the base 28, said cover threaded, as shown at 13,into a correspondingly tapped recess in a block 12 mounted on the base29, and with the upper end of the bolt having a head 14, preferablyknurled to permit manual'rotation of the same, to thus raise or lowerthe upper end of theyoke 61 and thereby rock the same on the shaft 30,to thus move the grinders S0 toward or from the cooperating'grinders 50.

Any suitable connection for this purpose between the adjusting bolt 1|and the hub 10 may be effected, but as herein shown I provide a forkedportion in the hub in which fork a block 15 is fitted, which block issecured by a set screw, or is formed integral with the adjusting bolt IIand thus moves the yoke upwardly or downwardly to rock the same on thepivot 30.

I provide a suitable and novel guiding element for the knife handle whenthe knife blade is positioned across the overlapping portions of thegrinders and and the contacting faces of the grinders 5| and BI. Forthis purpose, I attach a bracket 80 to the side and upper part of thearm 23, which bracket carries a pair of cylindrical bearings BI and 82,and spaced therebetween is a collar 83, which collar is secured by a setscrew to a shaft 85 of an adjusting screw, said shaft having a knurledturning handle 86 to rotate the same.

being of light metal construction and with an opening to fit over theadjusting screw 86 so that the cover can be swung off and on withoutinterference with the adjusting screw.

This cover 90 is also formed with an extension 93 to fit over theadjusting screw 1| and the head 14, as best shown in Figs. 2 and 3. Thetop of the cover 90 is preferably formed with an inwardly curved surface94-94 opening into a slot 95 of sufiicient area and in proper positionto permit the knife handle'and blade being operated on by the grinders,and which also protects the hands of the operator from contact with orinjury by the rotating gears or grinders.

I claim: 7

A portable power-driven knife sharpening unit of the kind described,comprising a motor carried in the lower part of said unit, two rotatableshafts each carrying a set of sharpening elements adapted to be rotatedby said motor, one of said shafts being mounted in fixed bearings, andthe other of said shafts being mounted in the arms of a pivoted bellcrank yoke, adjusting means to rock said yoke on its pivot, said sets ofsharpen ing elements including a plurality of overlapping grindingwheels arranged in staggered relation and a pair of grindingwheelsarranged in tangential relation to .operate simultaneously on aknife blade to be sharpened, manually adjustable knife handle guidemeans. positioned adjacent to said tangential grinders and adapted toseat 5 the heel of said blade in contact therewith, the adjusting meanson said bell crank yoke adapted to move one set of the sharpeningelements toward and from each other, and a removable protecting andguiding cover for said sharpening elements.

STEPHEN G. NICHOLS.

Name Date Capewell Oct. 23, 1877 Number Number 10 Number Name DateEcaubert Aug. 4, 1891 Dilg July 13, 1920 Nagy Sept. 5, 1933' Burns Jan.14, 1941 McBride Dec. 16, 1947 McBride Dec. 16, 1947 FOREIGN PATENTSCountry Date Switzerland Sept. 1, 1936 Great Britain Feb. 14, 1939

